Hallucinated URL

Why are URLs an especially easy thing to invent?

Because they are formulaic. A model that has seen thousands of examples of example.com/blog/what-is-x can produce a convincing address for a page nobody wrote, and the result passes every check a reader applies at a glance: the domain is right, the path reads sensibly, and the slug matches the topic. Only fetching it reveals anything.

Grounded answers reduce this, because the citation comes from something actually retrieved. Ungrounded ones do not, and an assistant answering from memory has no mechanism that distinguishes a remembered URL from a constructed one. The pattern is predictable enough to anticipate. Invented paths cluster on the shapes a site is expected to have and does not: a pricing page on a site with none, a documentation path that never existed, a /blog/what-is-x for the article you have not written.

What gets invented is a decent map of what an assistant expects to find on a site like yours. Reading it that way turns a defect report into a content plan, which is the only genuinely cheerful thing on this page. One caution before treating every invented path as demand: bots and scanners also generate 404s in bulk, and a path requested once by something with no referrer is noise. Look for repetition over weeks, and for paths whose shape matches your own conventions rather than somebody else’s.

What does a hallucinated URL cost you?

A visitor who tried. Somebody was interested enough to follow a link to your site and got a 404, which is a worse outcome than never being mentioned: the intent existed and your site failed to meet it. Because the invented paths are formulaic, they are also predictable, and they tend to cluster on the pages you have not written yet.

How do you turn them into traffic instead?

Watch your 404 log for paths you never published, and treat the repeated ones as a demand signal rather than as noise. A path an assistant keeps inventing is a page an assistant keeps wanting to cite, and you have three responses available: redirect it to the nearest real page, publish the page it was describing, or leave it alone if the request volume does not justify either.

The recommendation, and it is a position that could be wrong on a large site: redirect sparingly and publish more often. A redirect satisfies the visitor and teaches nothing, while the page it was asking for is a page somebody has now demonstrated demand for, at the exact URL an assistant already believes in.

Related terms

• AI HallucinationAn AI hallucination is a statement a language model produces confidently and fluently that is not true.
• AI Referral TrafficAI referral traffic is the visits that arrive at a site from an AI assistant rather than from a search results page.
• GroundingGrounding is the step that ties a model’s answer to sources it retrieved, so the reply can cite them rather than assert them.
• AI CitationAn AI citation is a link an AI assistant attaches to its answer, naming a page as a source.